1. Field of the Invention
This invention relates to a motor vehicle having at least two driven axles, means for selectively disconnecting one of said driven axles from the prime mover, and a brake system for braking the wheels of both or all said axles.
2. Description of the Prior Art
If the right-hand and left-hand wheels of motor vehicles having at least two driven axles have greatly different coefficients of friction, a braking of the vehicle may result in a yawing or swerving, i.e., in a turning about the vertical axis of the vehicle, so that the vehicle then exhibits an unstable behavior. In order to avoid this it has been proposed in U.S. Pat. No. 4,605,087 to disconnect one axle, usually the rear axle, from the prime mover before a braking is initiated. But that concept will eliminate the advantage that an all-wheel-driven vehicle will usually exhibit an improved response to braking. Besides, the disconnecting operations will frequently be performed and that the means for performing such operations will be highly loaded whenever they are operated.